get the second most recent git tag

Question

I need the sha of the second most recent git tag. When running

git show-ref --tags

i get

ab295f707bc42e8975fd4d87142ca436c0fac94f refs/tags/initial-commit-tag
1c816fc0895faeecd48b9b31e09ba825698f92a6 refs/tags/production-2018-03-06-001

which shows my two tags i currently have. How can i get it to output just ab295f707bc42e8975fd4d87142ca436c0fac94f?

I tried git rev-list --tags --max-count=1 --skip=1 but that apparently includes non tags as well, because when i run

git rev-list --tags --max-count=30 --skip=1

i get

d3d536c6745c823994b3fec8ce3b26caf2b4c6f5
08278f196cad30b5acbdd9d5f0baa58baab630bc
480513c6d94c6df52f49b91c5f90c39af4fc8f34
183a91321a85083fdf29b77bcbce5b9ca3932f12
e04e120be2f200bae88de37d1be2cebc8b07f74f
168b696f915adaea95c4e0d2a8cea68ea25538b2
0b9aa10a4f005f349e9553ac75552abc07723b95
befa7507836af93b1c765d957c65cbcf6ebea890
6850539077d82847907410d587ca3da047043915
a0a6d7b98c64ad318ff0d2c4252ac1ad94959bb2
3e91ed05db57b5dec23df0a465b9c8bc0a8dfe26
2341cf5a58974a9f57b0aa92a837e7857631f5cb
385a88d22c77cf26f21a906a2be65695528960b9
c7548f04d7b928eb7bf2f485aeb6fa78ef6846e9
a5abb21b1acb59617e3d69173d883c3e5f7db0f2
b0595fae8c8f697aa02dbd49d149da4f4efabad6
2c08455a1b86e1ba6de86844a83346262ab89e00

so there are not only tags in this list. How can i filter for just tags in here/make the first command workable to only show the second recent one?

Note: am on Mac/Linux, so bash piping would work as well.

EDIT:

In the end the --no-walk option wordked for me, so

git rev-list --tags --max-count=1 --skip=1 --no-walk

The accepted answer below is much more powerful though.

Answer 1

You could refactor a bit your git command and pipe it to sed to extract the data you need :

git for-each-ref --sort=-taggerdate --format '%(objectname)' refs/tags | sed -n 2p  

Explanation:

• git for-each-ref : documentation link. Displays information about refs.
  • --sort=-taggerdate : reverse sort the output by tag date
  • --format '%(objectname)' : we only output the hash
  • refs/tags: we only list the tags in refs/tags
• sed -n 2p: output only the 2nd line

Note that if you don't have a taggerdate on your tags, you can use other sort options, like creatordate (full list of available fields here).